1. Field
The present disclosure relates to an organic electrolyte solution and a redox flow battery including the same, and more particularly, to an organic electrolyte solution for a battery having high energy density, and a redox flow battery including the same.
2. Description of the Related Art
Secondary batteries are highly efficient energy storage systems which are widely used for mobile phones and large power storage devices. Specifically, secondary batteries are used in semiconductor and liquid crystal devices, acoustic devices, and information and communication devices such as mobile phones and laptop computers. More recently, secondary batteries are being used as power sources in hybrid vehicles.
Power storage systems for portable electronics and hybrid vehicles desirably provide a stable energy supply and high energy conversion efficiency. Recently, redox flow batteries are being considered to provide a secondary battery having larger capacity and improved durability, such as a capacity and durability suitable for grid power storage systems.
Unlike other batteries, an active material of the redox flow battery is in a liquid state instead of a solid state, and the redox flow batteries use a mechanism of storing and generating electric energy according to an oxidation/reduction reaction of catholyte and anolyte ions at a cathode and an anode, respectively.
In other words, the redox flow batteries include an electrolyte solution, wherein an active material of an electrode is dissolved in a solvent. The catholyte is oxidized and the anolyte is reduced when the redox flow battery including the catholyte and the anolyte, which have different oxidation states, is charged, and the electromotive force of the redox flow battery is determined by a difference between standard electrode potentials)(E0) of a redox couple of the catholyte and the anolyte. The catholyte and anolyte are supplied from respective electrolyte solution tanks by a pump. Oxidation and reduction of the electrolytes occurs simultaneously on the surfaces of the cathodes and anodes in the redox flow battery, similar to other types of batteries. Also, because the electrolyte solution tanks may be easily scaled, redox flow batteries may have power characteristics like fuel cells.
However, since the solubility of the catholyte and/or the anolyte of a redox flow battery may be insufficient, it can be difficult to obtain a redox flow battery having a desired energy density. Thus there remains a need for an improved electrolyte for a redox flow battery.